Hi nphsingh,
You asked about this same subject in a post a couple of days ago, and the issues that I mentioned are still the same....
Before you go spending too much time focusing on any particular 'difficulty level' of questions, it's important to define your current skills and your goals.
1) What is your score goal?
2) How have you been scoring on your practice CATs (including the Quant and Verbal Scaled Scores)?
3) When are you planning to take the GMAT.
It could be that the materials that you're asking about are not actually the materials that you *need*.
GMAT assassins aren't born, they're made,
Rich